Video including high definition (HD) video may be transmitted over wired paths and/or wireless paths. For instance, HD video may be transmitted over wireless digital visual interface (DVI) paths from a source to a player.
Regardless of how transmitted, the use of two clocks may be required when the video clock rate is different from the communication clock rate. The video clock refers to the rate at which the video data is encoded at a source and then decoded at a display, and the communication system clock refers to the clock rate of the transmission system. The source of video and the player of the video must use the same video clock, and similarly the transmitter and receiver of the communication system must use the same communication system clock.
How to ensure that the transmitter and receiver in a communication system use the same clock is well known and will not be further dwelt on. The transmission of data such as digital video data that moves to the beat of a different clock, however, is a relatively new technical challenge.
Heretofore, some video communication paradigms simply required the video clock to be related in some predefined way to the communication system clock. This way, there is no need to transmit any information about the video clock with the data, since the receiver system knows the predefined relationship the video clock has with the communication clock and can simply derive the video clock from the communication clock, for passing the video clock information on to the video player that requires it. Unfortunately, the requirement that the clock of the video system bear a predefined relationship to the clock of the communication system unnecessarily constrains the video system, and/or renders some video systems, which have video clocks that are established independently and arbitrarily from any communication system clock, unsuitable for transmission over the communication system. The present invention is directed to this observation, and more generally to the problem of transmitting data that uses a clock which is independent of the transmission system reference clock.